<template>
  <view>
    <!-- 渲染搜索框 -->
    <view class="search-box">
      <!-- focus:自动获取焦点，cancelButton：取消按钮状态，radius：圆角，@input：输入 -->
      <uni-search-bar @input="input" :radius="100" cancelButton="none" :focus="true"></uni-search-bar>
    </view>
    <view>
      <!-- 搜索建议列表 -->
      <!-- 判断数组长度在长度为0时展示搜索历史，不为0时展示搜索列表 -->
      <view class="sugg-list" v-if="searchResults.length !==0">
        <view class="sugg-item" v-for="(item,i) in searchResults" :key="i" @click="gotoDetail(item)">
          <view class="goods-name">{{item.goods_name}}</view>
          <uni-icons type="arrowright" size="16"></uni-icons>
        </view>
      </view>
      <!-- 搜索历史 -->
      <view class="history-box" v-else>
        <!-- 标题区域 -->
        <view class="history-title">
          <text>搜索历史</text>
          <uni-icons type="trash" size="17" @click="clean"></uni-icons>
        </view>
        <!-- 列表区域 -->
        <view class="history-list">
          <uni-tag :text="item" v-for="(item,i) in histories" :key="i" @click="gotoGoodsList(item)"></uni-tag>
        </view>
      </view>
    </view>
  </view>
</template>

<script>
  export default {
    data() {
      return {
        timer:null,
        kw:'',
        //搜索的结果列表
        searchResults:[],
        //搜索历史的数组
        historyList:['a','app','apple']
      };
    },
    onLoad(){
      this.historyList=JSON.parse(uni.getStorageSync('kw')||'[]')
    },
    methods:{
      input(e){
        clearTimeout(this.timer)
        this.timer=setTimeout(()=>{
          this.kw=e
          this.getSearchList()
        },500)
      },
      async getSearchList(){
        //判断搜索字符是否为空
        if(this.kw.length===0){
          this.searchResults=[]
          return
        }
        const {data:res} = await uni.$http.get('/api/public/v1/goods/qsearch',{query:this.kw})
        if(res.meta.status!==200)return uni.$showMsg()
        this.searchResults=res.message
        this.saveSearchHistory()
      },
      gotoDetail(item){
        // console.log(item.goods_id)
        uni.navigateTo({
          url:'/subpkg/goods_detail/goods_detail?goods_id='+item.goods_id
        })
      },
      saveSearchHistory(){
        //直接添加会造成元素重复
        // this.historyList.push(this.kw)
        
        //用set对象解决数组元素重复的问题
        //1.将Array数组转化为Set对象
        const set = new Set(this.historyList)
        //2.调用Set对象的delete方法，移除对应的元素
        set.delete(this.kw)
        //3.调用Set对象的add方法，向Set中添加元素
        set.add(this.kw)
        //4.将Set对象转化为Array数组
        this.historyList=Array.from(set)
        
        //调用uni.setStorageSync(key,value)将搜索历史记录持久化存储到本地
        uni.setStorageSync('kw',JSON.stringify(this.historyList))
      },
      clean(){
        this.historyList=[]
        uni.setStorageSync('kw','[]')
      },
      gotoGoodsList(kw){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?query='+kw
        })
      }
      
    },
    computed:{
      histories(){
        //获取一个内存无关的新数组存储翻转过后的数据,不能用元素组使用reverse方法，会修改原数组中的元素顺序
        return [...this.historyList].reverse()
      }
    }
  }
</script>

<style lang="scss">
.search-box{
  background-color: #C00000;
  position: sticky;
  top:0;
  z-index: 999;
}
.sugg-list{
  //容器上下间隔0，左右间隔5px
  padding: 0 5px;
  .sugg-item{
    //让两个view项处于一行
    display: flex;
    align-items: center;
    //两端贴边对齐
    justify-content: space-between;
    //文字大小
    font-size: 12px;
    //上下13px，左右0px
    padding: 13px 0;
    //每个item项设置一个灰色边框
    border-bottom: 1px solid #efefef;
    .goods-name{
      // 文字不允许换行
      white-space: nowrap;
      //溢出部分隐藏
      overflow: hidden;
      //文本溢出后，使用...代替
      text-overflow: ellipsis;
    }
  }
  .history-box{
    .history-title{
      display: flex;
      justify-content: space-between;
      
    }
  }
}
.history-box{
  padding: 0 5px;
  .history-title{
    display: flex;
    justify-content: space-between;
    height:40px;
    align-items: center;
    font-size: 13px;
    border-bottom: 1px solid #efefef;
  }
  .history-list{
    display:flex;
    flex-wrap:wrap;
    padding: 5px 0;
    .uni-tag{
      margin-top:5px;
      background-color: #efefef;
      border-color: #efefef;
      margin-right:5px;
      color:black;
      font-size: 13px;
      
    }
  }
}
</style>
